Safety-valve.



Z.E.GR0QK. SAFETY VALVE.

APPLICATION FILED AUG. 5, 1911. RBNEWED JUNE 10, 1914.

Patented Jan. 5, 1915.

n vanto@ ZENO E. CBOOK, OF DENVER, COLORADO.

SAFETY-VALVE.

Application filed. August 5, 1911, Serial No. 642,505. Renewed June 10, 15H4.

To all tix/mm it may concern:

Be it known that l, ZENO E. Cuoon, a citizen oit the United States, residing at Denver7 in the county oi Denver and State ot' Cidonulo, have invented new and useful Improvements ,iii Sa'fetyeValves, of which the 'following a specii'ication.

T his invention relates to safety valves and particularly to that type which are adapted to be used upon pressure cookers.

@ne of the particular features of the invention is its peculiar structure which renders the same as nearly perfectly sanitary as is possible.

it further object of the invention is the provision of springs which properly hold the valve upon its seat and which cannot become cramped or damaged, as is the case with compression springs used in the ordinary safety valve. The springs being arranged entirely out oi' the path of the escaping vapors are therefore free from corrosion by said vapors and thus render the valve more durable and sanitary.

Further objects of the invention will appear as the following specic description is read in connection with the accompanying drawing, which forms a part oi? this application, and in which Figure l is a side elevation. Fig. 2 is an edge elevation. Fig. 8 is a vertical sectional view.

Referring more particularly to the drawing, l represents the casing of the valve which is provided with a threaded nipple adapted to enter the top of the cooker and at its opposite end is provided with a valve seat 2 in which a ball valve 3 is seated. rThis ball valve is held upon the seat by means oi a cross bar 4 having a recess 5 formed in its center to receive the ball and being apertured at its outer ends to receive the ends of the tension springs 6, whose opposite ends are connected to the laterally extended arms T carried by the casing. The bar 4 is guided in its movements by means of separated ears 8 which extend up vertically from the casing on opposite sides of the ball seat and between which the bar d operates. `W ith the 7alve of this type the ball may be conveniently removed by simply disconnecting one of the springs from the arm 7 and lifting the bar in its guideway. After removing the spring the bar may be held upon the ball lightly so as to utilize the valve in the manner of a pet cock. All the parts may be Specification of Letters Patent.

Patented Jan. 59 T9315.;

Serial No. 844,361.

conveniently removed from the casing so that they may be readily cleaned and so that the casing may be properly cleaned.

The valve is made with a pop ed action so that when the steam reaches a certain predetermined pressure the ball will lift and allow the steam to escape until four or five pounds of steam pressure have es caped when the ball will recede with a snap thus preventing any further escaping of the steam until the pressure has again reached a point to cause the unseating of the valve. rllhe steam thus escapes for an interval of time with a -noise loud enough to be heard :from some distance, and when the valve is seated it is silent for an interval of time. This alternate silence and noise serves as a signal to warn the cook that the lire is too hot and should be regulated as to economize fuel and lier food values which are wasted when the steam escapes from the cooker. The pop off action is obtained by having a greater bearing surface for the action of the steam on the ball while the steam is escaping than when the ball is resting upon the seat as illustrated in the drawing. l/Vhen the ball is seated a circle with a diameter a--o represents the point of contact between the ball and the seat. The steam pressure exerts a lift on the ball of an amount equal to the product of the steam pressure for a unit of area by the area of the circle whose diameter is 1f-Z). When the steam pressure reaches an amount sul'hcient to overcome the downward thrust on the ball, and the weight of the ball., the ball rises slightly and the .steam rushes out illing the space around the ball represented in the cross section by the triangles GEA and DFB. The action of the steam then exerts a lift on a circle whose diameter is o-cZ. The ball then remains suspended by the action of the steam until the pressure is reduced so the product of the pressure per unit of area by the area of the large circle becomes less than the downward thrust of the springs and the weight of the ball when the ball drops to the seat and shuts oil' all further escaping of the steam until the pressure` has again reached the pop oill point.

Having thus described the invention, what l claim as new is l. A safety valve comprising a casing having a threaded attaching nipple, a seat formed in the easing, a ball valve resting tending stationary arms carried by said casing and having downturne'd ends, a ball valve having a portion arranged Within said casing upon said seat, separate spaced parallel ears rising from'said easing upon each side of said valve, a har slidably mounted between the said ears and having a rec-ess to engage said ball, and expansion springs connected to the ends of said bar and downturned ends of said arms, and one of said springs being removably engaged With said arm to prevent tilting of said bar or the escaping of steam When desired.

In testimony vvhereoil I aix my signature in presence of tWo Witnesses.

ZENO E. CROOK.

Witnesses:

J. S. CRooK, E. C. HENDRICK.

Copies of this patent may 'be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

